Oncology Flashcards
What causes cancer?
age
physical carcinogens- UV and ionizing radiation
chemical carcinogens- asbestos, tobacco smoke, aflatoxin arsenic
Biological carcinogens- viruses, parasites, bacteria
How many deaths are caused by lifestyle factors?
30%
Is liver cancer common?
No, becoming slightly more common though because of alcohol. Most cancer in the liver are spread there not start there
What are some characteristics of cancer cells?
Evading apoptosis
insensitivity to anti-growth signals
Tissue invasion and metastasis
Limited replicative potential
Sustained angiogenesis
Self-sufficiency in growth signals
What does telomerase do that cancer cells dont express?
Can divide limitlessly unlike normal cells in which telomeres shorten over time when dividing and eventually cannot divide anymore
How do we target replicative immortality in cancer cells?
Telomerase inhibitors
Is pancreatic cancer survivable?
Yes but very low survival rate
What is the most ideal treatment of cancer?
Surgery- cutting out a solid tumour
How does radiotherapy work?
Very high energy beams focused on a small area of tissue using electrons. The energy tears molecules apart and ionizes water molecules to form ROS that cause DNA damage.
How does chemotherapy work?
Inhibits cell division- non selective killing of rapidly dividing cells- induction of apoptosis through cell damage
What is chemotherapy most suitable for?
Aggressive, fast growing cancer
What is hormonal therapy best for?
Breast, prostate cancer
What is hormonal therapy for breast cancer?
Blocking oestrogen receptors. 2/3 of breast cancers express oestrogen
What does hormone therapy do in breast cancer? Will it cure it?
It wont cure it, but it can be used after surgery or after surgery and chemo, or before surgery. After surgery aim is to prevent it coming back, before surgery is to shrink a large cancer. It may be used without surgery if someone chooses or cant have surgery so that the cancer grows slower
Why is the CNS a bad target for chemotherapy?
BBB
